The purpose of the Rodent Animal Biosafety Level 3 (ABSLs) Core is to provide investigators with the opportunity to advance research in bioterrorism and emerging infectious diseases through the use of a fully operational rodent facility. Small animal models have played a critical role in investigations of infectious diseases of importance to humans. In particular, rodent models have been successfully used to develop and test vaccines and other prevention strategies, to evaluate the efficacy and toxicity of therapeutic agents, to develop diagnostics, and to explore pathogenesis. The Rodent ABSLs Core at UC Irvine consists of a stateof- the-art, fully certified ABSLs facility offering investigators resources to conduct research on Category A, B and C pathogens, including those designated as select agents. Although designed primarily for small animal work, the ABSL3 is organized so that non-animal work with select agents can also be accommodated. Through a recharge procedure, use of the facility will be offered to investigators in academia and in industry throughout region IX and beyond;a committee and a process for allocating temporary space to potential users has been developed. Moreover, the laboratory is set up to provide not only space but also trained, dedicated in-house personnel to conduct experiments designed and supervised by Principal Investigators at UC Irvine or other institutions. The facility will offer the opportunity to conduct aerosol challenge studies of NIAID category A, B, or C priority pathogens and emerging infectious diseases in order to investigate pathogenic mechanisms and develop vaccines and rapid diagnostic tests of inhaled organisms. The Rodent ABSLs Core sets out to accomplish two specific aims: i) Maintain an infrastructure to ensure the availability of a regional ABSLs facility for use by investigators in academia and industry. The Core will maintain a process for space allocation and a recharge unit for facility use and for technical support;2) Establish and maintain a small animal aerosol challenge unit in the ABSLs facility. Experiments will be conducted to validate the unit, characterize biophysical properties of aerosolized bacteria, and develop a mouse model of pulmonary infection to advance research in inhaled infections. The Rodent ABSLs Core will serve as a critical regional resource for collaborative pathogenesis, vaccine and diagnostic studies.